20 NATURALISTS' ASSISTANT. 



insects. It is not necessary to detail the method of using it, 

 as any one will readily find out for himself. 



For collecting stinging insects a pair of forceps, fig. 6, made 

 of wire, the distal extremities of which are bent into broad 

 blades covered with netting, will prove very convenient, es- 

 pecially as there is no danger of being stung. The bee or 

 other insects are caught between the blades while resting on a 

 flower, and while a prisoner is pinned ; and then, the blades 

 being opened, the pin is readily drawn from the meshes of 

 the netting. 



An umbrella is indispensable in collecting certain forms of 



insects. It is held spread open 

 in an inverted position beneath 

 the branches of some tree or 

 shrub, then the foliage is beaten 

 with a stick, and the insects 

 IG ' ' drop and are caught. This is 



especially valuable for collecting certain Coleoptera, Spiders, 

 Microlepidoptera, Psocidae, etc. 



For killing insects the most convenient plan is to take a 

 wide-mouthed bottle and place in the bottom a piece of cya- 

 nide of potassium (a dangerous poison) . Then some plaster 

 of Paris is mixed to a stiff paste with water and poured 

 over the cyanide. The plaster soon sets and holds the 

 chemical firmly, while its porosity allows the fumes of prussic 

 acid to pass readily into the vacant portion of the bottle. 

 The bottle after thus being prepared should be allowed to 

 stand open for a day to allow the moisture from the plaster 



